1. Field of the Invention
The present invention relates to a TV apparatus, its control method, a network TV system, a computer program and a recording medium readable by a computer, and more in particular, it relates to a display of an image and the like using IEEE1394.
2. Related Background Art
In recent years, not only offices, but also various associations have begun taking an active role to realize a home network. As one example, the IEEE has been promoting the standardization of a technology for transferring serial data at high speed for a long distance (IEEE1394.b). Besides, VESA (Video Electronics Standards Association) has undertaken a study of a communication protocol based on the IEEE1394b. in Home_Networking Committee.
Moreover, the 1394TA (Trade Association) is right in the midst of formulating a communication protocol based on the IEEE1394-1995 and its expanded regulation (IEEE1394.a-2000 regulation and the like).
On the other hand, the practical application of a digital TV has been carried out with Europe as a center. This digital TV digitally packets an image, an audio data and the like, and has a capability of simultaneously transferring a plurality of programs at the same bandwidth as the broadcast bandwidth of the conventional analog TV. In addition, because of the digitalization of the image and the audio (packet), random access to that data is easily accomplished, and therefore, there is a merit of being able to simultaneously store and reproduce or easily edit and transfer the data. For example, the digitally packeted image and audio data are directly recorded on the storage medium randomly accessible such as a hard disc and a semiconductor, and while that data is being reproduced, it is possible to perform a control for recording another data on a position of another recording medium.
By utilizing the above-described merit, if the digital TV has a built-in recording medium which is randomly accessible, a new function can be realized. For example, heretofore, in case of leaving while enjoying a program, the data broadcast while leaving has not been enjoyed, but if the recording medium which is randomly accessible is used, the data during leaving is recorded on the recording medium, and upon return from leaving, the left data is reproduced from the recording medium, and moreover, even during reproducing, the data can be continuously recorded on the recording medium, and therefore, the user can enjoy the TV without missing the data in the state where the broadcast content is delayed. As one example of this technology, Japanese Patent Application Laid-Open No. H09-322085 can be cited.
However, according to the above-described Japanese Patent Application Laid-Open No. H09-322085, when the user who left the digital TV returns and enjoys the digital TV again, though it is possible for him to enjoy the left image and the like, in order to enjoy the left image and the like, he has to enjoy by the left digital TV. That is, when the user leaves the digital TV, he is unable to enjoy the left image and the like by another digital TV reached (by the user). This has prevented the user from comfortably enjoying the TV.
Further, when a plurality of users simultaneously use an apparatus storing the image data and the storage apparatus of a server, there develops a problem in the bandwidth of a network. Particularly, in an IEEE1394 home network, when a transfer of 100 m or more is performed, its bandwidth ends up dropping to the level of 100 Mbps. Hence, a storage control method to reduce a data transfer preferably on the network is required by providing a receiving function and a storing function in each digital TV. What is meant by the IEEE1394 home network is a home network configured from an apparatus conforming to an IEEE1394-1995 regulation and its expanded regulation (IEEE1394.a-2000 regulation and the like).
Further, in the digital TV, not only the image and audio data, but also, for example, the audio and visual information such as helping enjoy the information and the like on an agent function for executing the selection of favorite programs from many channels realized by the information on the channels frequently enjoyed or the digitalization of the TV are different from the left information, and therefore, the user is confused in operating a reached digital TV.
The present invention has been carried out in view of the above described problem, and the object of the invention is to provide a TV apparatus, its control method, a network TV system, a computer program and a recording medium readable by a computer, which enables the user to enjoy the image and the like after he left without being embarrassed in operating the reached TV apparatus even in the case where the user leaves the TV apparatus and enjoys audio-visual contents by another reached TV apparatus.